This fact sheet describes how to eliminate bermudagrass from future vegetable fields using a sorghum-sudangrass cover crop.

This presentation discusses the management of soil fertility under organic regulations.

This handout discusses points to consider when blending organic fertilizers. It contains several tables of nutrient contents of different organic fertilizers.

Extensive bibliography, step-by-step outline, and list of common materials giving carbon:nitrogen ratio for each.

This is a presentation by Brian Freking from the livestock track of the 2012 Oklahoma Beginning Farmer & Rancher Program.  It covers the purpose of soil sampling, how (and how not) to take a sample, how to interpret test results, and how to use liming to adjust soil pH.